Understanding the Piezoelectric Response of Eu3+ Doped (Na0.41K0.09Bi0.5) TiO3: A Lead-free Piezo-luminescent Material

The piezoelectric and photoluminescence studies on $\mathrm{E}\mathrm{u}^{3+}$ doped $(\mathrm{N}\mathrm{a}0.41\mathrm{K}_{0.09}\mathrm{B}\mathrm{i}_{0.5-\mathrm{x}}\mathrm{E}\mathrm{u}_{\mathrm{x}})\mathrm{T}\mathrm{i}\mathrm{O}_{3}[\mathrm{x}=0.00$, 0.005, 0.01, 0.015, 0.02 and 0.03] ceramics have been carried out to explore its applications are piezo-luminescent material. The low-field piezoelectric response reveals optimum response near $\mathrm{x}=0.010$. A typical butterfly strain curve with maximum positive strain of 0.7% for $\mathrm{x}=0.01$. Higher doping levels results in a gradual reduction in the low and high field piezoelectric response. Further, the photo-luminescence of $\mathrm{E}\mathrm{u}^{+3}$ doped NKBT shows gradual increase in the intensity corresponding to the ${}^{5}\mathrm{D}_{0}\rightarrow^{7}\mathrm{F}_{2}$ transition with $\mathrm{E}\mathrm{u}^{+3}$ content in the sample. The present study also reveals that $\mathrm{E}\mathrm{u}^{3+}$ doped $(\mathrm{N}\mathrm{a}0.41\mathrm{K}_{0.09}\mathrm{B}\mathrm{i}_{0.5-\mathrm{x}}\mathrm{E}\mathrm{u}_{\mathrm{x}})\mathrm{T}\mathrm{i}\mathrm{O}_{3}$ with $\mathrm{x}=0.01$ is promising composition for piezo-luminescence applications.